Surgical Knife Providing Enhanced Blade Visualization

Abstract

A surgical knife providing enhanced visualization includes an elongated handle, a footplate and a non-transparent blade. The footplate is supported on the handle and has a foot positioned to ride along tissue of a surgical site. The non-transparent blade has a cutting edge and is supported on the handle with at least a portion of the cutting edge extending beyond the foot, to expose the cutting edge for making an incision. The non-transparent blade is visually observable with ease, particularly along a line of sight passing through translucent tissue adjacent an incision. The foot may be constructed of a transparent material to allow direct observation of the blade or the surgical site via a line of sight passing through the transparent foot. These features provide a knife well-suited to making precisely placed and precisely curved incisions of the type required for astigmatic keratotomy and limbal relaxation procedures.

1 . A surgical knife comprising:
 an elongated handle;   a footplate supported on the handle, said footplate comprising at least one foot having a guide surface positioned to ride along tissue of a surgical site; and   a non-transparent blade having a cutting edge, said blade being supported on said handle with at least a portion of said cutting edge extending beyond said guide surface of said foot.   
   
   
       2 . The knife of  claim 1 , wherein said non-transparent blade is constructed from a translucent material. 
   
   
       3 . The knife of  claim 2 , wherein said at least one foot is constructed from a transparent material. 
   
   
       4 . The knife of  claim 2 , wherein said translucent material is selected from the group consisting of a sapphire, a naturally-occurring diamond, a synthetic diamond, a colored diamond, and a black diamond. 
   
   
       5 . The knife of  claim 1 , wherein said non-transparent blade is constructed from a visually opaque material. 
   
   
       6 . The knife of  claim 5 , wherein said at least one foot is constructed from a transparent material. 
   
   
       7 . The knife of  claim 5 , wherein said visually opaque material selected from the group consisting of a metal or a ceramic. 
   
   
       8 . The knife of  claim 7 , wherein said metal is selected from the group consisting of stainless steel, aluminum and titanium. 
   
   
       9 . The knife of  claim 1 , wherein said at least one foot is constructed from a transparent material. 
   
   
       10 . The knife of  claim 1 , wherein said footplate comprises a pair of feet and said blade is positioned to extend between said pair of feet, and wherein each of said pair of feet is constructed from a transparent material. 
   
   
       11 . The knife of  claim 9 , wherein said transparent material has a refractive index substantially similar to that of corneal tissue. 
   
   
       12 . The knife of  claim 9 , wherein said transparent material is selected from the group consisting of glass, polycarbonate and poly[methyl-methacrylate]. 
   
   
       13 . The knife of  claim 1 , further comprising an adjustment mechanism adjustable to vary the amount of the cutting edge extending beyond said guide surface of said foot. 
   
   
       14 . The knife of  claim 1 , wherein said adjustment mechanism comprises a micrometer. 
   
   
       15 . A surgical knife comprising:
 an elongated handle;   a footplate supported on the handle, said footplate comprising at least one foot constructed from a transparent material, said foot having a guide surface positioned to ride along tissue of a surgical site; and   a blade having a cutting edge, said blade being supported on said handle with at least a portion of said cutting edge extending beyond said guide surface of said foot.   
   
   
       16 . A method for performing surgery, comprising:
 plunging a non-transparent blade into human tissue;   visually observing a portion of the blade positioned within the human tissue by direct observation along a line of sight extending through tissue adjacent the blade; and   guiding the blade to make an incision in human tissue while visually observing the portion of the blade through the tissue adjacent the blade.   
   
   
       17 . The method of  claim 16 , wherein the plunging the non-transparent blade into human tissue comprises plunging a translucent or opaque blade into ocular tissue. 
   
   
       18 . The method of  claim 17 , wherein guiding the blade to make an incision in human tissue comprises guiding the blade to make an arcuate incision selected from the group consisting of an astigmatic keratotomy incision and a limbal relaxing incision. 
   
   
       19 . A method for performing surgery, comprising:
 grasping a surgical knife comprising:
 an elongated handle; 
 a footplate supported on the handle, the footplate comprising at least one foot having a guide surface positioned to ride along tissue of a surgical site, the at least one foot being constructed from a transparent material; 
 a blade having a cutting edge, the blade being supported on the handle with at least a portion of the cutting edge extending beyond the guide surface of the foot; 
   plunging the blade into human tissue;   visually observing a surgical site by direct observation along a line of sight extending through the transparent foot; and   guiding the blade to make an incision in human tissue while visually observing the portion of the blade through the transparent foot.   
   
   
       20 . The method of  claim 19 , further comprising:
 withdrawing the blade from the human tissue when the blade is visually observed to have reached a visible stopping point marking on the human tissue.   
   
   
       21 . The method of  claim 20 , wherein the plunging the blade into human tissue comprises plunging a translucent or opaque blade into ocular tissue. 
   
   
       22 . The method of  claim 21 , wherein guiding the blade to make an incision in human tissue comprises guiding the blade to make an arcuate incision selected from the group consisting of an astigmatic keratotomy incision and a limbal relaxing incision.